INSERT PLATE INPUT ON PV ELITE

[James Bonding]

Hi I would like to seek your help. I am doing a design for caustic scrubber vessel. Before the vessel is using a reinforcing pad but now the client opted to change it to insert plate. The nozzle size is 16"and it's located on the cone section of the vessel. My question is how to consider the insert plate in PV Elite like how to input it.

Thank you so much....

 

[jtseng123]

Just design as usual with re-pad. The insert plate thickness is the cone + re-pad. The size of the insert plate will be the OD of the re-pad + 3:1 taper section to the cone. You may want to use square or rectangular insert plate with round corners to ease fabrication.

 

[Some Curious Guy]

You can enter the local shell thk as insert plate thickness near the bottom left corner of the nozzle design dialogue box. I could not find any input for the diameter of insert place. For that I suggest you enter the reinforcement limit ( bottom right corner ) equal to diameter of insert plate minus it tapered portion.
With that being said I am wondering why the client insist on an insert plate. Their use has a lot of fabrication challenges and would add to your lead time. You would need to purchase and form an additional thicker plate. You would be lucky if you get an exact length and breadth of thicker insert plate from the mill stocks. The insert plates needs to be welded to shell / cone before cutting the nozzle hole. If you do other way round your nozzle location would be off since weld distortion would somewhat crumple the shell area in the vicinity of insert plate. I have heard shops spending more time in correcting any forming misalignment and weld distortion of shell / cones / head having insert plate. Hence shops I know usually shy away from insert plate and they prefer to use a SR nozzle instead.
You can do an alternate design with a self reinforced nozzle option. You can use provision of Appendix 46 of Div 1 to optimize nozzle size and hub thickness if cost and nozzle hub to shell thickness is a concern. Then you can compare both option considering cost, ease of procurement , fabrication difficulty and lead time.